Searched the archives here and all related posts indicate that the "start error" message on the display is related to the immobilizer technology. My wifes 2001 ML320 just experienced this error. My local dealer said either the key or the control module, Tele-Assist said the same thing. She was out of town. Tele-assist dispatched a truck, towed her to the local dealership. After a lot of diagnosis trouble, they claimed it was the battery. Claimed to have tested the battery and it was bad. I would have thought there would have been a lot of solenoid clacking, lights flashing, etc. Only thing that happened when she tried to start the car was this "start error" message came up.

Is this problem really fixed, or did it just go away and they took this opportunity to sell an out-of-towner a battery? I.e. has anyone seen the actual cause of this error message to be the battery?

I had a same "start error" message yesterday morning when trying to start in my ML 270cdi. I could just hear "clak" four/five times. I thought the battery was weak so I gave some power from 911 for few minutes but it did the same thing. A/C, navi, fan and lights work like they should. I´m going to buy new battery tomorrow to see if it will fix the problem.

When I was test driving a 2002 ML 320, the battery was drained, and it showed a Start Error, they put it on the battery booster and it started perfectly, and when we took the car home for a week it never had any more problems.

I have had a few isolated instances (3 in 60K miles) when the engine cranks but does not start and the display sates "start error". I remove the key and try again and it has always started on the second try.
Are you guys saying repeated starting attempts result in a "start error" every time or the engine does not even crank while trying?

Are you guys saying repeated starting attempts result in a "start error" every time or the engine does not even crank while trying?

Yes, I just went down and tried again and same thing, now just looks like the battery is pretty much on its last. I disconnected the battery too for few minutes just to check that option. Hopefully it is the battery as I have my ML in -2 floor with no access for Tow truck. ML is as big it is possible to fit in, only way to get it out is driving.

the over-head center light kill-switch was in the off position (which shows doors open) and hit it now interior light go on now. will check and see if the key unlocks the doors now in a little while. the key unlock button would not unlock doors and when inserted key to unlock I thought I would check the unlock button when they were already unlocked and the unlock button locked the doors. Just might be a security thing. very smart vehicles. backed it upon ramps to view underside. car would not start. rocked it off ramps and started right up. not sure if this is a fix but found a fix for the interior lights not working. reset dash, reset key, reset gas pedal, reset windows, reset radio, reset did not fix the start error. had throttle position code and evap code, and gas cap code(po123, po400, po442)